In WiMAX (Worldwide Interoperability for Microwave Access) Forum, WiMAX has been established based on IEEE (Institute of Electrical and Electronic Engineers) 802. 16e Standard.
The WiMAX is characterized by achieving a fast communication speed of 200 Mbs or more in spite of wireless communication, and by providing services such as guaranteeing of a band, for a MS (Mobile Station: terminal), to acquire a transmission rate appropriate to a QoS (Quality of Service) class to which the MS belongs.
A configuration of a wireless communication system of the WiMAX is disclosed in, for example, Non-patent Literature 1. FIG. 1 shows an example of a configuration of the wireless communication system of the WiMAX.
As shown in FIG. 1, the wireless communication system of the WiMAX includes MSs 10-1˜10-L (L is an integer of 2 or more), BSs (Base station) 20-1˜20-M (M is an integer of 2 or more) and ASN-GW (Access Service Network-Gateway) 30A located in an ASN, and AAA (Authentication, Authorization, Accounting) server 40A located in CSN (Connectivity Service Network). FIG. 1 shows only components related to the present invention.
BSs 20-1˜20-M are base stations that perform wireless communication with MSs 10-1˜10-L.
AAA server 40A is a server apparatus that authenticates, gives permission to, and makes charges to MSs 10-1˜10-L.
ASN-GW 30A is a gateway apparatus that manages subordinate BSs 20-1˜20-M and MSs 10-1˜10-L. In other words, ASN-GW 30A centrally controls the ASN.
When the number of MSs 10-1˜10-L increases, to deal with the increase, there is a method of simply increasing the number of ASN-GWs 30A.
However, this method has a problem in which the costs for facility investment increase. As an alternative method, therefore, a method of increasing the number of MSs 10-1˜10-L that is allowed entry to one ASN-GW 30A is considered promising.
A configuration of ASN-GW 30A is disclosed in, for example, Non-patent Literature 2. FIG. 2 shows an example of a configuration of ASN-GW 30A.
As shown in FIG. 2, ASN-GW 30A includes ASN-GW DP (Decision Point) 31A and ASN-GW EP (Enforcement Point) 32A.
ASN-GW DP 31A is a C-plane processing unit that processes a C plane (Control Plane) for controlling signaling to transfer a control signal. A burst load is accordingly applied on ASN-GW 31A during entry of MSs 10-1˜10-L to the ASN or during hand-over.
ASN-GW EP 32A is a U-plane processing unit that processes a U plane (User Plane) for transferring user data of MSs 10-1˜10-L that is included in its own entry. Thus, a steady load tends to be applied on ASN-GW EP 32A.
Therefore, in the WiMAX Forum, as a method of increasing the number of MSs 10-1˜10-L that is allowed entry to one ASN-GW 30A, a method of setting a configuration ratio of ASN-GW DP 31A and ASN-GW EP 32A to 1:N (N is an integer of 2 or more) is discussed.